fs: add do_readlinkat() helper; remove internal call to sys_readlinkat()
Using the do_readlinkat() helper removes an in-kernel call to the
sys_readlinkat() syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/fs/stat.c b/fs/stat.c
index 873785d..f8e6fb2 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -379,8 +379,8 @@
return error;
}
-SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
- char __user *, buf, int, bufsiz)
+static int do_readlinkat(int dfd, const char __user *pathname,
+ char __user *buf, int bufsiz)
{
struct path path;
int error;
@@ -415,10 +415,16 @@
return error;
}
+SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
+ char __user *, buf, int, bufsiz)
+{
+ return do_readlinkat(dfd, pathname, buf, bufsiz);
+}
+
SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
int, bufsiz)
{
- return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
+ return do_readlinkat(AT_FDCWD, path, buf, bufsiz);
}